3D-Gaming Benchmark Results
I decided to only use Quake2 and Expendable and I ran both at 640x480 to avoid a major impact of the graphics card on the performance numbers. Quake3 is too hard on the graphics cards and Half-Life's 'Smokin'-demo scores unrealistically low results. Quake2 was executed with the 3DNow!-patch and is thus 3DNow!-enhanced, but not ISSE-enhanced. Expendable is one of the few games that are already using ISSE and it has some minor 3DNow!-optimization too. You will be able to see the difference below:
Both CPU's scale well in Quake2's crusher-demo, at least up to 650 MHz core clock. Above that, Athlon is again probably impacted by the graphics card, the AGP-bandwidth or the memory bandwidth, so that the graph becomes a bit flatter, although not too much. Pentium III 650 can't even reach the scores of an Athlon 550 in Quake2.
The story changes with Expendable and the ISSE-usage. You can see that Pentium III is not far behind Athlon, getting pretty close at 650 MHz. A Pentium III 700 could probably reach an Athlon 700 in Expendable, but we shouldn't forget that Rage did certainly not use the latest 3DNow!-instructions included into Athlon's instruction set. At the same time it's important to remember that Expendable was used by Intel's PR at the Pentium III-launch. It wouldn't be surprising if Rage put a whole lot of work into the ISSE-enhancements. Still, Expendable shows that the battle between Athlon and Pentium III becomes closer as soon as a game favorites ISSE-enhancements over 3DNow!-enhancements. That's where Intel will try to intervene, making sure that software uses ISSE and not 3DNow!. It's the only way to make Pentium III look good or at least reasonable against Athlon.